Answer:
y = x*sqrt(Cx - 1)
Step-by-step explanation:
Given:
dy / dx = (x^2 + 5y^2) / 2xy
Find:
Solve the given ODE by using appropriate substitution.
Solution:
- Rewrite the given ODE:
dy/dx = 0.5(x/y) + 2.5(y/x)
- use substitution y = x*v(x)
dy/dx = v + x*dv/dx
- Combine the two equations:
v + x*dv/dx = 0.5*(1/v) + 2.5*v
x*dv/dx = 0.5*(1/v) + 1.5*v
x*dv/dx = (v^2 + 1) / 2v
-Separate variables:
(2v.dv / (v^2 + 1) = dx / x
- Integrate both sides:
Ln (v^2 + 1) = Ln(x) + C
v^2 + 1 = Cx
v = sqrt(Cx - 1)
- Back substitution:
(y/x) = sqrt(Cx - 1)
y = x*sqrt(Cx - 1)
It would use 2.83 gallons of gas for a 2 hour trip
Answer: Anna could buy 5 sweatshirts for $75.
Step-by-step explanation:
lets figure out the price of one sweatshirt.
45/3 = 15
one sweatshirt is $15
5*15=75
so 5 sweatshirts cost $75
Factor the following:x^4 + 4 x^3 + 6 x^2 + 4 x + 1
The coefficients match the 5^th row of Pascal's triangle, so x^4 + 4 x^3 + 6 x^2 + 4 x + 1 = (x + 1)^4:Answer: (x + 1)^4
Answer: 74
Step-by-step explanation:
48+75+25/2